Abstract

Electronic and optical properties of graphene and graphitic ZnO (G/g-ZnO) nanocomposites have been investigated with density functional theory. Graphene interacts overall weakly with g-ZnO monolayer via van der Waals interaction. There is no charge transfer between the graphene and g-ZnO monolayer, while a charge redistribution does happen within the graphene layer itself, forming well-defined electron-hole puddles. When Al or Li is doped in the g-ZnO monolayer, substantial electron (n-type) and hole (p-type) doping can be induced in graphene, leading to well-separated electron-hole pairs at their interfaces. Improved optical properties in graphene/g-ZnO nanocomposite systems are also observed, with potential photocatalytic and photovoltaic applications.

Received 15 January 2013Accepted 07 March 2013Published online 28 March 2013

Acknowledgments:

This work is partially supported by the National Key Basic Research Program (Grant No. 2011CB921404), by National Science Foundation of China (NSFC) (Grant Nos. 21121003, 91021004, 21233007, 20933006), by Chinese Academy of Sciences (CAS) (Grant No. XDB01020300), and by USTCSCC, SC-CAS, Tianjin, and Shanghai Supercomputer Centers.